Refactor color management and UI components for consistency

- Updated color references in various widgets to use the new `opaquePrimary` color for better visual consistency.
- Refactored `ColorsManager` to improve color definitions and removed redundant color declarations.
- Enhanced UI elements across multiple dialogs and widgets to ensure a cohesive design language.

This change promotes maintainability and aligns with the updated color scheme.

lib/pages/analytics/modules/occupancy/widgets/heat_map_tooltip.dart

@@ -34,7 +34,7 @@ class HeatMapTooltip extends StatelessWidget {
               style: context.textTheme.bodySmall?.copyWith(
                 fontSize: 12,
                 fontWeight: FontWeight.w700,
-                color: ColorsManager.whiteColors,
+                color: ColorsManager.white,
               ),
             ),
             const Divider(height: 2, thickness: 1),
@@ -43,7 +43,7 @@ class HeatMapTooltip extends StatelessWidget {
               style: context.textTheme.bodySmall?.copyWith(
                 fontSize: 10,
                 fontWeight: FontWeight.w500,
-                color: ColorsManager.whiteColors,
+                color: ColorsManager.white,
               ),
             ),
           ],